In general, rotary tools and oscillating tools are light-weight, handheld power tools capable of being equipped with a variety of tool accessories and attachments, such as cutting blades, sanding discs, grinding tools, and many others. These types of tools, referred to hereinafter as power tools, typically include a generally cylindrically-shaped main body that serves as an enclosure for an electric motor as well as a hand grip for the tool. The electric motor is operably coupled to a drive member, referred to herein as a tool holder, that extends from a portion of the main body of the power tool. The electric motor is configured to rotate and/or oscillate the tool holder at relatively high frequencies. The tool holder in turn is configured to secure different accessory tools so that as the tool holder is driven to move by the electric motor, an accessory tool secured to the holder is driven to perform work on a workpiece.
To enable a secure connection between a tool holder for a power tool and accessory tools for use with the power tool, tool holders and associated accessory tools are provided with drive structures that mate to secure an accessory tool to a tool holder. For example, a tool holder of a power tool is provided with a tool drive structure that comprises one or more protrusions having a predetermined configuration and/or arrangement with respect to the tool holder. An accessory tool for use with the tool holder is provided with an accessory drive structure defining one or more openings and/or recesses that are configured and/or arranged complementary to the features of the tool drive structure of the tool holder. When the accessory tool is placed onto the tool holder, the protruding features of the tool drive structure are received in the corresponding openings and/or recesses defined by the accessory drive structure. A clamping device, such as a clamping screw, is then used to clamp the accessory tool to the tool holder thereby locking the tool drive structure and the accessory drive structure into engagement with each other.
While the use of complementary drive structures is effective in securing an accessory tool to the tool holder of a power tool, variations in tool drive structures incorporated into the tool holders of various power tools limits the ability of an accessory tool configured for use with the tool holder of one power tool to be secured to the tool holder of other power tools.